Mercury-pump.



PATENTED JULY 18, 1905.

S. B. FLIGHTNER. MERCURY PUMP. APPLICATION FILED 0012a. 1902.

Q IE ANDREW a GRAHAM cm, LITHOGRAPHER5, wAsnmuTou. n. c.

pipe leadin to which is shown at 9.

UNITED STATES Patented July 18, 1905.

PATENT OFFICE.

STANWOOD E. FLICHTNER, OF ENGLEWOOD, NEW JERSEY, ASSIGNOR, BY MESNE ASSIGNMENTS, TO COOPER HEWITT ELECTRIC COMPANY, A

CORPORATION OF NEW YORK.

MERCURY-PUMP.

SPECIFICATION forming part of Letters Patent No. 794,707, dated July 18, 1905.

Application filed October 23, 1902. Serial No. 128,423.

To aZZ whom it may concern:

Be it known that I, STANwooD E. FLIGHT- NER, a citizen of the United States, and a resident of Englewood, in the county of Bergen and State of New Jersey, have invented certain new and useful Improvements in Mercury-Pumps, of which the following is a specification.

My invention relates to improvements in mercury-pumps, particularly such as are adapted to create a vacuum of the desired degree of exhaustion in gas or vapor lamps of the well-known Hewitt type.

The invention relates to various details in the construction and arrangement of a mercury-pump apparatus, all of which will be fully described in the specification which follows, and more particularly pointed out in the claims.

My invention is illustrated in the accompanying drawing, which is an elevation and part section of'an apparatus embodying my improvement.

Referring to the drawing, 1 is a shallow circular reservoir of iron having a mercury duct or trough 2 cast on it in one piece. The reservoir 1 is covered by a glass dome-shaped cover 3, and the duct 2 may also have a cover. At intervals along the duct 2 are arranged outlet-cocks, one of which is shown in the drawing at 4. The cock 4 consists of a stem 4, screwed into a valve-seat 5. Upon opening the cock mercury flows from the duct or trough 2 into fall-tubes 6 7. These fall-tubes are of peculiar construction and will be specifically described later on. To the fall-tubes are attached, by rubber corks and the mercury seals, a lamp 8 and a connection 8 to a mechanical air-pump, tge

long vertical portion of the fall-tube (shown at 7) ends inside a cup 10, having a flexible outlet-pipe 11, joining the cup 10 at about the middle of its length. The outlet-pipe 11 5 empties into a general catch-basin 12, to

which the outlets of all the pumps lead. The catch-basin 12 is connected by an outletpipe 13 with an inlet-valve 14 of an air-tank 15. The valve 14 is normally held closed-by a spring 17, as shown. From near the bottom of the air-tank 15 runs a pipe 16, which extends into the reservoir 1 and ends above the level of the mercury therein. Into the top of the air-tank 15 runs an air-pipe 24, the connection of which to a source of compressed-air supply 26 is controlled by an electropneumatic valve 1.8, operated by a set of dry batteries 19 through the medium of a diving-bell contact 21. 22.

The course of the mercury is as follows: From the tank 1 it flows along the duct or trough 2, through the cock 4 5, down the fall-tubes 6 7, into the cup 10, through the outlet pipe or tube 11 into the catch-basin 12 and the outlet 13. The mercury accumulates in the catch-basin 12 until it is of sufficient height above the valve 14 to overcome the action of the spring 17 and open the valve, permitting the mercury to run into the air-tank 15 and gradually filling the latter until such a level is reached as is necessary to complete the circuit of the batteries 19 through the valve 18. When this happens, the valve operates and allows compressed air to enter the air-tank 15 through the pipe 24. This air, pressing down upon the surface of the mercury in the tank, instantly closes the valve 14 and forces the mercury through the pipe 16 up into the reservoir 1. This operation continues until the circuit of the valve 18 is broken, whereupon, the supply of compressed air being interrupted, the flow of the mercury through the pipe 16 ceases. The action of the valve 18 when it is restored to the position where it shuts off the sup ly of compressed air from the pipe 24 also opens a vent in the said pipe, thereby releasing the compressed air above the mercuryin the tank 15 and allowing the column of mercury in the tube 16 to fall to the level of that in the tank 15. While the compressed air has thus been forcing the mercury from the tank 15 into the reservoir 1, the pumps have continued to cause mercury to flow from the reservoir and the same has collected in the catch-basin 12. Upon the removal of the air-pressure, as described above, the valve 14 reopens by reason of the pressure of the accumulated mercury above the valve in the pipe leading thereto. Under the proper conditions the described series of operations 7 repeats itself, and the lamps 8 are gradually brought to the desired state of exhaustion. The-diving-bell valve 21 22 is adapted to open the valve 18 when the mercury in the air-tank is high and to close it when the mercury is low. The valve consists of a contact-terminal 22, passing through an insulating-packing 23 in the top or cover 45 of the tank 15, and air-tight bell or cylinder 21, which projects below the level of the conductor 22, but ends above the bottom of the tube 16. When the mercury in the tank 15 rises above the bottom of the bell 21 on' the outside thereof, the mercury inside the bell will not rise as rapidly, owing to the air confined within the be 1. Eventually, however, the mercury inside the bell will make contact with the conductor 22 and the valve 18 will be opened to turn on the air. The resultin increase of pressure outside the bell 21 will force the mercury up inside the bell, continuing the contact between the mercury and the conductor 22. This contact will continue until the level of the mercury outside the bell 21 descends below the lower edge of the said bell, whereupon bubbles of air will rise inside the bell, the mercury therein will flow out, the connection with the conductor 22 will be broken, the valve 18 will be closed,

and the air will be shut off.

The tank 15 is provided with the top for convenience in inspecting the parts with- The top overhan s The with the parts attached to the top by simply The valve 14, normally closed by a spring 17 and opened by the weight of the mercury column resting on the valve, is an improvement 'over the usual valve which remains ;normally open and which is shut off by the back pressure of the mercury after the air is turned on.

With the latter form of valve the mercury is liable to spurt out through the valve-opening, often being scattered over the floor instead of being retained in the catchbasin.

At the upper end of the fall-tube are three cups 4O 41 42, to which connections are made by means of rubber corks, pushed far enough into the tube to allow mercury seals over the corks. The arm 6 of the tube is provided with a pocket 43, into which the mercury falls before entering the tube 7. This insures the mercury being fed into thetube 7 in large drops instead of being spattered into the tube in small drops. Tube 7 is peculiarly shaped, being large at its upper end and tapering slightly below the mercury-inlet'to a bore .14 to .15 of an inch. This diameter is then continued five inches or more to a point about an inch or more above the height at which the mercury would stand in the tube 7 under atmospheric pressure. This is the point where the falling drops coalesce and form a solid stream. As I have said, the bore .14 to .15 of an inch extends to within an inch or so of this coalescing-point and then contracts to a bore of .1 to .12 of an inch. It is well known that a glass tube is not cylindrical but conical in shape, the cone being very acute. It has been found best, however, to have. that portion of the fall-tube which has a bore of .1 to .12 of an inch arranged with a smaller end upward, the bore becoming wider and wider as the mercury approaches the cup 10.

The terminal which cooperates through the mercury with the terminal 22 may be either the tank 15 itself or the cup or bell 21. In

case the tank is used for this purpose the cup or bell 21 may be ofinsulating material.

In order to provide an alarm or indicator to show when the air-pressure has become too low for efficient action, I insert in the compressed-air-supplypipe 27 a low-pressure alarm device, the c1rcuit-closer of which is illustrated at 25. of a U-shaped tube having one open leg, connected to the air-supply pipe 27, and one closed leg 28. The bend of the U is filled with mercury. The latter is connected by a wire 30 with one terminal of an electric bell 31 the other terminal of the bell being connected with an insulated contact-piece 32, runningarranged as to leave the circuit of the bell 31 open, Whereas on a reduction of the pressure in the open leg below a good operative pressure the mercury may be caused to flow back into the open leg sufficiently to close the circuit of the bell 31 and sound the alarm.

The improvements in fall-tube system consist in making the same separable from the lamp and the cup 10, making the fall-tube 7 perfectly straight, so that it can readily be cleaned, and giving it the peculiar shape already described.

I claim as my invention- 1. In a mercury-pump, a mercury-reservoir, a mercury-circuit, and a fall-tube in- The circuit-closer consists cluded in the circuit, the said fall-tube being detachable and having four different diameters at different portions of its length, the uppermost diameter being comparatively large, the two next diameters bein successively shortened and the lowermost iameter being larger than the contracted portion.

2. In a mercury-pump, a mercury-reservoir, a mercury-circuit, and a fall-tube included in the circuit, the said fall-tube being detachable, and being flaring at each end.

3. In a mercury-pump, a mercury-reser- Voir, a mercury-circuit and a fall-tube ineluded in the circuit, the said fall-tube being flaring at its opposite ends.

Signed at New York, in the county of New York and State of New York, this 20th day of October, A. D. 1902.

STANWOOD E. FLICHTNER.

Witnesses:

WM. I-I. OAPEL, Tnos. H. BROWN. 

